Electrode line

ABSTRACT

An implantable electrode line having a proximal and a distal end, an outer electrode line surface and an electrode line longitudinal axis. The implantable electrode line is characterized in that the electrode line in the region of the distal end has a surface region with a microstructure, the surface region being provided for lateral contact with a vessel wall and being arranged at a spacing relative to the distal end which measures a plurality of electrode line diameters. The microstructure is formed by a plurality of microstructure elements which are arranged on the electrode line surface and which are distributed over the surface region both in the longitudinal direction and also in the peripheral direction. The microstructure elements are adapted, upon contact with a vessel wall, to counteract displacement of the electrode line along the electrode line longitudinal axis.

CROSS-REFERENCE TO RELATED APPLICATIONS/INCORPORATION BY REFERENCE

This U.S. Patent Application is a continuation of U.S. patentapplication Ser. No. 10/883,030 filed on Jun. 30, 2004 which claimspriority to and the benefit of German patent application 103 31 106.8filed Jul. 4, 2003.

TECHNICAL FIELD

Certain embodiments of the present invention relate to implantableelectrode lines. More particularly, certain embodiments of the presentinvention relate to an implantable electrode line having a proximal anddistal end, an outer electrode line surface and an electrode linelongitudinal axis.

BACKGROUND

Electrode lines, for example for cardiac pacemakers, suffer from theproblem of electrode dislocations. Previous solutions for fixing anelectrode line in the heart and in vessels are for example pre-shapedelectrode lines which brace the electrode in vessels. Also known arehelixes or screws which are disposed at the distal end of the electrodeline on the electrode and which are adapted to fix the electrode to amyocardium by screwing therein. Also known are openings in the distalregion of an electrode line, which are adapted to anchor the electrodeline in the trabecula arrangement of a cardiac chamber.

The state of the art also includes hooks which are disposed at thedistal end or on the electrode line and which are adapted to fix theelectrode line to the myocardium.

The applicants' patent application WO97/31678 describes an electrodearrangement having a ventricular electrode which has hook-shaped fixingmeans at the distal end of the electrode.

DE 69430417 T2 discloses an electrode system in which the electrode lineis of a flexible nature in order to form a loop between the atrialelectrode and the ventricular electrode. In the proximity of the atrialelectrodes that electrode line has a first passive fixing device in theform of hooks and in the proximity of the ventricular electrodes at thedistal end it has a fixing device with two hooks.

Further limitations and disadvantages of conventional, traditional, andproposed approaches will become apparent to one of skill in the art,through comparison of such systems with the present invention as setforth in the remainder of the present application with reference to thedrawings.

SUMMARY

In accordance with an embodiment of the present invention, animplantable electrode line is provided which permits secure fixing ofthe electrode line in the heart and in vessels.

Such an embodiment is attained by an electrode line of the kind setforth in the opening part of this specification, which in the region ofthe distal end has at least one surface region with a microstructure,the surface region being provided for lateral contact with a vessel walland being arranged at a spacing relative to the distal end whichmeasures a plurality of electrode line diameters. The microstructure isformed by a plurality of microstructure elements which are arranged onthe electrode line surface and which are distributed over the surfaceregion both in the longitudinal direction and also in the peripheraldirection and which extend with a radial directional component,preferably outwardly. The microstructure elements are of a radial extentwhich is a fraction of the electrode line diameter and are adapted, uponcontact with a vessel wall, to counteract displacement of the electrodeline along the electrode line longitudinal axis.

The advantage of such an electrode line is that many microstructureelements which measure a fraction of the electrode line diameter andwhich are distributed on a surface region of the electrode line afford agreater degree of adhesion than for example in the case of an electrodeline which has only one or some hooks at the surface for fixing theelectrode line.

In an embodiment of the present invention, the microstructure elementsare in the form of microbristles, wherein the microbristles are arrangedat a predetermined angle relative to the electrode line surface. Theangle can be for example 90°. This advantageously provides that theelectrode line is secured against longitudinal axial displacementequally in the direction of the proximal end and also in the directionof the distal end.

In a further embodiment, the microbristles are arranged in parallelrelationship with the electrode line longitudinal axis, and in aparticularly preferred feature the microbristles are oriented with adirectional component facing towards the proximal end of the electrodeline. This advantageously provides that the electrode line can be easilyintroduced in the implantation procedure and an increased level ofresistance to displacement of the electrode line towards the proximalend is afforded by the orientation towards the proximal end. As analternative to this embodiment a microstructured surface region may haveboth microstructure elements which are oriented with a directionalcomponent facing towards the proximal end and also such microstructureelements which are oriented with a directional component facing towardsthe distal end of the electrode line. Preferably the microbristles areoriented along the longitudinal axis of the electrode line alternatelywith a proximal and a distal directional component. That advantageouslyprovides for fixing of the electrode line in respect of displacementalong the longitudinal axis of the electrode line, both in a directiontowards the proximal end of the electrode line and also in a directiontowards the distal end thereof.

In another alternative embodiment of the present invention, themicrobristles are arranged at a predetermined angle relative to theelectrode line surface and are each oriented in mutually parallelrelationship at a predetermined angle relative to the longitudinal axisof the electrode line. In this embodiment the microbristles arepreferably oriented with a directional component facing towards theproximal end of the electrode line. That advantageously provides thatthe electrode line can be screwed into a vessel by rotation about thelongitudinal axis in the peripheral direction. Preferably the bristlesare adapted to bear flat against the electrode surface in thescrewing-in operation. A rotational movement in opposite relationship tothe screwing-in direction provides for fixing of the electrode line,repeated rotational movement in the screwing-in direction causes releaseof the electrode line.

Alternatively the microstructure elements are in the form of knobs whichare adapted to cling to a vessel wall by adhesion. For that purpose theknobs preferably have a flat adhesion surface which is arrangedperpendicularly to the radial direction of the electrode line. Whencoming into contact with a suitable pressure against a vessel wall, asufficiently thin film of moisture can be produced between the adhesionsurface and the vessel wall. That produces adhesion forces which fix theelectrode line to the vessel wall.

In a further preferred feature the knobs are in the form of suctioncups. For that purpose, instead of the flat adhesion surface, the knobsmay have a concavely shaped adhesion surface.

In another embodiment the microstructure elements are in the form ofscales with a scale edge. Preferably the scales are arranged at apredetermined angle, further preferably an acute angle, relative to theelectrode line surface, in such a way that the scale edge is spaced fromthe surface of the electrode line. In a further preferred feature thescales are arranged in such a way that at least one edge portion of thescale edge has an orientational component extending perpendicularly tothe longitudinal axis of the electrode line. This advantageouslyprovides that, on coming into contact with a vessel wall, the electrodeline is easily displaceable in one direction along the longitudinal axisof the electrode line while in the direction opposite thereto, by virtueof the scale edges engaging into the vessel wall, there is an increasedlevel of resistance to longitudinal axial displacement.

In a further embodiment, the scales have at least one prong or tooth atthe scale edge. That prong can advantageously engage into the vesselwall, in addition to the scale edge, and thus provide a furtherincreased level of resistance to longitudinal axial displacement.

The microstructure elements can be disposed on or shaped from thesurface of the electrode line. Preferably the microstructure is producedin a microstereolithographic process, for example by deposition on asubstrate. The substrate can be applied to the electrode line surface ormay be formed by the electrode line surface itself. Alternatively asurface region with a microstructure may also be produced by amicrostereolithographically produced form.

An electrode line may have one or more surface regions with amicrostructure, in which respect an embodiment or a combination ofvarious embodiments of microstructure elements such as for examplemicrobristles, scales, knobs or the embodiments of microstructureelements illustrated in the Figures can be implemented on just oneelectrode line.

Suitable materials for the electrode line are for examplepolytetrafluoroethylene (PTFE), silicone, polyimide, ethylenechlorotrifluoroethylene, ethylene tetrafluoroethylene (ETFE),polypropylene or polyurethanes. The microstructures can be producedjointly with the electrode line or a portion of the electrode line in aninjection molding process, in which respect the microstructures can beappropriately incorporated in an injection molding mold.

For easy introduction of the electrode line into a lumen, an electrodeline may have a longitudinally axially displaceable sheath which can bearranged on the electrode line in such a way as to cover themicrostructure and, in the situation of use, to release themicrostructure by retraction in a proximal direction.

These and other advantages and novel features of the present invention,as well as details of an illustrated embodiment thereof, will be morefully understood from the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in greater detail with reference tothe Figures.

FIG. 1 shows the distal end of an electrode line having an electrodeline surface and surface regions which each have a respectivemicrostructure,

FIG. 2 shows various embodiments of microstructure elements,

FIG. 3 shows an arrangement by way of example of microbristles on anelectrode line,

FIG. 4 shows portions of an electrode line with various embodiments ofmicrostructure elements which are in the form of scales,

FIG. 5 shows diagrammatically illustrated embodiments of knobs, and

FIG. 6 shows an embodiment in which an electrode head is cord-connectedto a distal end of an electrode line by way of a connecting line.

DETAILED DESCRIPTION

FIG. 1 diagrammatically shows the distal end of an electrode line 100having an electrode line surface 101 and surface regions 105 and 106which each have a respective microstructure. The surface region 105 isarranged at a spacing 104 from an electrode 103 disposed at the distalend of the electrode line. The surface region 105 with a microstructureoccupies only a part of the surface of the electrode line, in theperipheral direction. In this example, the drawing also shows aperipherally extending surface region 106 which covers the outerelectrode line surface 101 over the entire peripheral direction. In thisembodiment the surface region 106 is arranged at a spacing 102 from theelectrode 103 at the distal end. FIG. 1 shows two alternativeconfigurations of surface regions—peripherally extending therearound andnot extending therearound—jointly on one electrode line. An electrodeline in accordance with the invention may have at least one surfaceregion 106 extending entirely therearound in the peripheral direction ofthe electrode line or at least one surface region 105 which does notextend entirely therearound.

As an alternative thereto, an electrode line in accordance with theinvention may have a plurality of surface regions 106 extending entirelytherearound in the peripheral direction of the electrode line or aplurality of surface regions 105 which do not extend entirelytherearound. A combination of surface regions 106 extending entirelyaround the electrode line and surface regions 105 which do not extendentirely therearound, on an electrode line, afford various alternativeconfigurations which are not illustrated here. The spacings 102 and 104may both amount to several electrode line diameters 110 and arediagrammatically illustrated in this example. The surface regions 106and 105 have a microstructure, the microstructure being formed by aplurality of microstructure elements which are arranged on the surfaceof the electrode line and which are distributed over the surface regionboth in the longitudinal direction and also in the peripheral direction.Various embodiments of microstructure elements are illustratedhereinafter in FIG. 2.

FIG. 2 shows a diagrammatic illustration of various embodiments ofmicrostructure elements. Those microstructure elements are of a radialextent beyond the surface of the electrode line, said extent being afraction of the electrode line diameter. The microstructure elements areadapted to counteract displacement of the electrode line in thelongitudinal direction, when they are in contact with a vessel wall.

Provided on the electrode line surface 201 are for examplemicrostructure elements 203 which are in the form of curvedmicrobristles. The microbristles 203 are curved with a directionalcomponent facing in the proximal direction 215. As a result, upondisplacement of the electrode line in the proximal direction 215, themicrobristles 203 produce an increased level of resistance todisplacement of the electrode line in the distal direction 216.

The microbristles can also be in the form of straight microbristles 205.These straight microbristles 205 are arranged at a predetermined anglerelative to the surface 201 of the electrode line, in such a way thatthey have an orientational component in the proximal direction 215.

The microbristles 207 are also straight and are arranged inperpendicular relationship to the electrode line surface 201. Thatprovides for an equally high level of resistance upon displacement ofthe electrode line in the proximal direction 215 and in the distaldirection 216.

The microbristles 209 are disposed on the electrode line surface 201and, at the end remote from the electrode line surface 201, have a hook210 which is shaped in the proximal direction 215. The hook 210 isadapted to engage into a vessel wall upon displacement of the electrodeline in the proximal direction 215 and thereby to produce a particularlyhigh level of resistance to displacement of the electrode line in theproximal direction 215.

The microbristles 211, like the microbristles 203, are also curved inthe proximal direction 215 and, at the end remote from the electrodeline surface 201, have a star-shaped branching configuration 212. Byvirtue of that configuration, upon coming into contact with a vesselwall, the microbristles 211 can particularly effectively engage intosame and thereby produce a high level of resistance to displacement ofthe electrode line in the proximal direction 215.

FIG. 3 diagrammatically illustrates an embodiment by way of example ofmicrobristles on an electrode line. FIG. 3 illustrates portions of anelectrode line 300, on the electrode line surface 301 of which aredisposed microbristles. The microbristles 303 are oriented at apredetermined angle relative to the electrode line surface 301 with adirectional component in the proximal direction 215.

In a further example microbristles 305 are arranged at a predeterminedangle relative to the electrode line surface 301 and are oriented with adirectional component in the proximal direction 215. The microbristles305 are also oriented in respective mutually parallel relationship at apredetermined angle relative to the longitudinal axis of the electrodeline so that, upon rotational movement of the electrode line in theperipheral direction 309 the microbristles 305 are anchored in a vesselwall when in contact therewith. Upon rotational movement of theelectrode line in the direction 310 opposite to the peripheral direction309 the microbristles 305 can be released from the condition of beinganchored in the vessel wall again.

The microbristles 307 are arranged orthogonally on the electrode linesurface 301. By virtue of that arrangement, an equally high level ofresistance is opposed to displacement movement upon displacement of theelectrode line in the proximal direction 215 and also upon displacementof the electrode line in the distal direction 216.

FIG. 4 diagrammatically shows portions of an electrode line 400 withvarious embodiments of microstructure elements which are in the form ofscales. The embodiments illustrated in FIG. 4 are shown in part jointlyon one electrode line portion. An electrode line may have a respectiveone of the illustrated alternative configurations or a combination ofvarious alternative configurations.

The scales 403 are oriented at a predetermined angle relative to theelectrode line surface 401 in the proximal direction 215. The scales 403have an edge which extends in perpendicular relationship to thelongitudinal axis of the electrode line and which has a toothedconfiguration 402. That toothed configuration is adapted to particularlyeffectively engage into a vessel wall and be anchored therein, upondisplacement of the electrode line in the proximal direction 215.

In a further example, scales 405 with a round edge are arranged inmutually juxtaposed relationship extending around an electrode line inthe peripheral direction thereof. The scales 405 form rings on theelectrode line surface 401, which are spaced from each other. Shownfurther to the right on that portion is an embodiment in which scales407 with a rounded-off edge are arranged in such a way that scales whichoccur in succession in the longitudinal axial displacement arerespectively displaced relative to each other in the peripheraldirection by half a scale width. Also arranged on the portion in theperipheral direction in mutually juxtaposed relationship are scales 409with a round scale edge, wherein the scale edge has prongs 411 which areoriented in the proximal direction 215 at at least one edge portionextending in the peripheral direction. Alternative configurations (notshown) of an electrode line can include a respective one of thealternative scale configurations 405, 407 or 409. A combination of thealternative scale configuration 409 with the alternative scaleconfiguration 407 on one electrode line or a combination of thealternative scale configuration 409 with the alternative scaleconfiguration 405 on one electrode line are possible alternativeembodiments.

FIG. 5 diagrammatically illustrates embodiments of knobs. The knobembodiments 502 and 503 are disposed on an electrode line surface 501and in this example are diagrammatically illustrated in a side view as asection.

The knob 507 is in the form of a portion of a cylinder and has acircular adhesion surface 508 which is adapted to cling to a vessel wallby adhesion.

The knobs 502 and 503, like the knob 507, can be of a cylindricalconfiguration. In the case of the knob shape 502 the adhesion surface504 is flat. In the case of the knob 503 the adhesion surface 505 is ofa concave shape and is thus in the form of a suction cup.

In a variant design (not shown), as an alternative to the circularshape, the adhesion surface can also be in the form of a polygon.

An electrode line in accordance with various embodiments of the presentinvention can have a combination of surface regions which extendentirely therearound or which do not extend entirely therearound, withany respective combination of the above-indicated alternativeconfigurations of microstructure elements in the form of microbristles,scales or knobs.

A further development of the invention is diagrammatically illustratedin FIG. 6. In this embodiment an electrode head 607 is cord-connected tothe distal end of an electrode line by way of a connecting line 605. Inthe region of the distal end 600 the electrode line has a surface region603 with a microstructure. In this example the surface region 603 is ofsuch a nature as to extend around the electrode line in the peripheraldirection. in this embodiment the connecting line 605 is sealed off inrelation to the electrode line body at the distal end thereof by asealing mass 604, for example a silicone sealing mass. Both theelectrode 607 and also the surface region 603 at the distal end 600 ofthe electrode line have a microstructure 603 formed by microstructureelements. The microstructure elements of the microstructure 602 arepreferably of an electrically conductive nature, for example theelectrode head 607 may contain the electrode line material and have agold or platinum layer at the surface thereof. The gold or platinumlayer can be applied by vapor deposition or sputtering. This embodimentadvantageously permits a relative movement along the longitudinal axisof the electrode line between the electrode head 607 and the distal end600 of the electrode line. The microstructure elements of themicrostructures 602 and 603 can be embodied in the form ofmicrobristles, knobs or scales in one of or a combination of theabove-described embodiments and arrangements. In an alternativeembodiment (not shown) the electrode line, similarly to FIG. 6, has anelectrode head which does not have any microstructure. The electrodehead is thus in the form of a freely floating electrode, preferably inthe form of a ventricular electrode.

In a development of the invention the microstructure of the surfaceregion of the electrode line is such that body tissue can grow into thesurface region.

While the invention has been described with reference to certainembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted withoutdeparting from the scope of the invention. In addition, manymodifications may be made to adapt a particular situation or material tothe teachings of the invention without departing from its scope.Therefore, it is intended that the invention not be limited to theparticular embodiment disclosed, but that the invention will include allembodiments falling within the scope of the appended claims.

1. An implantable electrode line comprising: a proximal end; a distalend; an outer electrode line surface; and an electrode line longitudinalaxis, wherein the electrode line in a region of the distal end includesa surface region with a microstructure, the surface region beingprovided for lateral contact with a vessel wall and being arranged at aspacing relative to the distal end which measures a plurality ofelectrode line diameters, and wherein the microstructure is formed by aplurality of microstructure elements which are arranged on the electrodeline surface and which are distributed over the surface region both in alongitudinal direction and also in a peripheral direction and which havea component extending radially, wherein the microstructure elements areof a radial extent which is a fraction of the electrode line diameterand are adapted, upon contact with a vessel wall, to counteractdisplacement of the electrode line along the electrode line longitudinalaxis.
 2. The implantable electrode line as set forth in claim 1 whereinthe microstructure elements are in the form of microbristles, whereinthe microbristles are oriented at a predetermined angle relative to theelectrode line surface.
 3. The implantable electrode line as set forthin claim 1 wherein the microstructure elements are oriented in parallelrelationship with the electrode line longitudinal axis.
 4. Theimplantable electrode line as set forth in claim 2 wherein themicrobristles are oriented in parallel relationship with the electrodeline longitudinal axis.
 5. The implantable electrode line as set forthin claim 2 wherein the microbristles are arranged at a predeterminedangle relative to the electrode line surface and are respectivelyoriented in mutually parallel relationship at a predetermined anglerelative to the electrode line longitudinal axis.
 6. The implantableelectrode line as set forth in claim 3 wherein the microstructureelements are arranged at a predetermined angle relative to the electrodeline surface and are respectively oriented in mutually parallelrelationship at a predetermined angle relative to the electrode linelongitudinal axis.
 7. The implantable electrode line as set forth inclaim 4 wherein the microbristles are arranged at a predetermined anglerelative to the electrode line surface and are respectively oriented inmutually parallel relationship at a predetermined angle relative to theelectrode line longitudinal axis.
 8. The implantable electrode line asset forth in claim 2 wherein the microbristles are oriented with adirectional component facing towards the proximal end of the electrodeline.
 9. The implantable electrode line as set forth in claim 3 whereinthe microstructure elements are oriented with a directional componentfacing towards the proximal end of the electrode line.
 10. Theinplantable electrode line as set forth in claim 4 wherein themicrobristles are oriented with a directional component facing towardsthe proximal end of the electrode line.
 11. The implantable electrodeline as set forth in claim 5 wherein the microbristles are oriented witha directional component facing towards the proximal end of the electrodeline.
 12. The implantable electrode line as set forth in claim 6 whereinthe microstructure elements are oriented with a directional componentfacing towards the proximal end of the electrode line.
 13. Theimplantable electrode line as set forth in claim 7 wherein themicrobristles are oriented with a directional component facing towardsthe proximal end of the electrode line.
 14. The implantable electrodeline as set forth in claim 1 wherein the electrode line surfacecomprises the microstructure elements.
 15. The implantable electrodeline as set forth in claim 1 wherein the electrode line surface does notcomprise the microstructure elements.
 16. An implantable electrode linecomprising: a proximal end; a distal end; an outer electrode linesurface; and an electrode line longitudinal axis, wherein the electrodeline in a region of the distal end includes a surface region with amicrostructure, the surface region being provided for lateral contactwith a vessel wall and being arranged at a spacing relative to thedistal end which measures a plurality of electrode line diameters, andwherein the microstructure is formed by a plurality of microbristleswhich are arranged on the electrode line surface and which aredistributed over the surface region both in a longitudinal direction andalso in a peripheral direction and which have a component extendingradially, wherein the microbristles are of a radial extent which is afraction of the electrode line diameter and are adapted, upon contactwith a vessel wall, to counteract displacement of the electrode linealong the electrode line longitudinal axis.
 17. An implantable electrodeline comprising: a proximal end; a distal end; an outer electrode linesurface; and an electrode line longitudinal axis, wherein the electrodeline in a region of the distal end includes a surface region with amicrostructure, the surface region being provided for lateral contactwith a vessel wall and being arranged at a spacing relative to thedistal end which measures a plurality of electrode line diameters, andwherein the microstructure is formed by a plurality of scales which arearranged on the electrode line surface and which are distributed overthe surface region both in a longitudinal direction and also in aperipheral direction and which have a component extending radially,wherein the scales are of a radial extent which is a fraction of theelectrode line diameter and are adapted, upon contact with a vesselwall, to counteract displacement of the electrode line along theelectrode line longitudinal axis.